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Nuclear Power 101

What is nuclear power?

Nuclear power is an energy technology that harnesses the powerful forces that hold together the nucleus of an atom.

Scientific advances in the first half of the 20th century led to the discovery that the nuclei of certain radioactive elements, such as uranium, could be broken into smaller components in a process called nuclear fission—"splitting the atom"—releasing enormous amounts of energy.

The first practical use of nuclear fission was to create nuclear weapons, but peaceful uses of the technology, including power generation, were rapidly developed in the decades after World War II.

How does nuclear power work?

In a typical nuclear reactor, uranium fuel rods release neutrons, which bombard other fuel rods to create a controlled nuclear fission chain reaction. This chain reaction produces large amounts of heat, which is used to drive electricity-generating steam turbines in much the same way that heat from coal combustion is used in a coal-fired power plant.

How much of our electricity comes from nuclear power?

In the US, about a fifth of our electricity is generated by nuclear power, making nuclear power the third largest electricity source after coal and natural gas.

Nuclear power has been controversial. What is the UCS position on it?

UCS is neither pro- nor anti-nuclear power. Nuclear power has one advantage over other non-renewable energy technologies: it contributes very little to global warming emissions. For this reason, an expansion of nuclear power would help address global warming.

However, this advantage must be weighed against the added risks to human health, the environment, and global security that nuclear power creates, as well as the nuclear industry’s failure to show that it can operate cost-effectively without the help of government subsidies.

Our focus at UCS is on working toward more effective regulation of U.S. nuclear power to protect the public from its hazards. As long as nuclear power remains part of our energy mix, we must do a better job of making it safer.

What are the risks of nuclear power?

There are two major kinds of risk associated with nuclear power:

Safety risks. A serious accident at a nuclear power plant could release large amounts of dangerous radiation, with disastrous consequences for the environment and an increased risk of cancer for those exposed to the radiation.

Security risks include both the risk of sabotage and terrorist attacks on nuclear power plants and the risk that nuclear materials will be stolen and used to create nuclear weapons.

It is the job of the Nuclear Regulatory Commission (NRC) to minimize these risks by making and enforcing rules that the nuclear power industry must follow. UCS closely follows, and sometimes criticizes, the NRC's performance in protecting the public.

What can we do to make nuclear power safer?

There are several things that can be done to reduce nuclear power risks, and UCS is urging policymakers to act on these solutions:

The NRC needs to do a better, more consistent job of enforcing existing safety rules.

Spent nuclear fuel, which has been allowed to accumulate in pools because of delays in finding a permanent waste storage site, should be moved as quickly as possible to dry casks to reduce the risk of a serious accident.

Security standards at nuclear power plants should be updated and enforced to reduce the risk of a successful attack or act of sabotage.

The United States should not pursue a reprocessing program. Reprocessing creates a risk of theft of materials that can be used to make weapons, and is not an effective solution to the nuclear waste problem.